Process of manufacturing carbazol derivatives



FREDERICK WILLIAM ATACK, OF CHARLESTON, WEST VIRGINIA,

PROCESS OF MANUFACTURING CAR-BAZOL DERIVATIVES.

No Drawing.

To all whom it may concern Be it. known that I, FREDERICK WVILLIAM ATAUK, a subject of the King of Great Brit ain, residing at Charleston, county of Kane- 6 wire, State of Vest Virginia, have invented certain new and useful Improvements in a Process of Manufacturing Carbazol Derivatives; and I do hereby declare the following to be a full, clear, and exact description of 10 the invention, such aswvill enable others skilled in the art to which it appertains to make and use the same.

This invention relates to processes of manufacturing carbazol derivatives; and it relates particularly to a process of preparing alkyl, aryl or alkaryl derivatives of car.- bazol, more especially the important alkyl derivatives, in a simple, efiicient, and economical manner.

29 I have found that many carbazol derivatives of the type above set forth can be easily prepared by suspending a metal compound of carbazol, such as potassium compound of carbazol (which will be referred 95 to herein as metal carbazol and potassium carbazol for the sake of convenience), in pulverized or otherwise finely divided condition in a liquid medium, most desirably a solvent of the derivative to'be $9 produced, that is substantially inert or inactive so far as concerns the procedure here in question; and then subjecting the metal carbazol in suspension to the action of any suitable agent for introducing an alkyl, aryl or alkaryl group in place of the metal of the metal carbazol, to produce the corresponding carbazol derivative. Where the solvent or other liquid medium employed as a suspension vehicle is one from which it 40 is desirable to separate the carbazol derivative eventually obtained, this can be accomplished in any suitable manner as, for example, by distillation in case the liquid medium employed is volatile, although I do not restrict myself to the use of a volatile liquid medium. Inorder to more fully explain the principles upon which thelinvention is based, the manufacture of ethyl carbazol will now 59 be described as an illustrative exampleem- Application filed June 22, 1922. Serial No. 570,192.

bodying the invention in especially desirable and important practical form. Potassium carbazol, which may be obtained in the known manner by fusing a mixture of carbazol and caustic potash (with suflicient water) in proper proportions, is introduced in pulverized condition into a relatively large volume of benzene, contained in a reaction vessel equipped with suitable stirring or agitating means and a reflux condenser, 0 and the mixture is agitated to obtain a uni form suspension of the pulverized potassium carbazol in the liquid vehicle. In a typical instance, potassium carbazol obtained from one (1) kilo of carbazol is thus suspended in three (3) liters of benzene. A sufficient. quantity of a suitable ethylating agent, such asdiethyl sulfate, say about 800 cc. in. the present example, is now added gradually during constant agitation ofthe mixture in '70 the reaction vessel. The mixture is boiled under reflux until the ethylation is substantially complete. The potassium carbazol is converted into ethyl carbazol, which latter dissolves partly or Wholly in the benzene. 75 When the reaction is substantiallyflor sufficiently complete, the benzene soletioniof ethyl carbazol together with any un-dgissoiaed ethyl carbazol is decanted or otherwise separated from the potassium sulfate and the solvent is removed by steam distillation or:- otherwise. The ethyl carbazol thus obtained may be purified in any suitable .manner, as by recrystallization from alcohol, the purified product having a melting point of 67-68 C.

It will be seen that the describe-d method is free from complications and can be carried out easily and quickly. The yield is good and a product of excellent purity can be made.

lVhile the processhas been described more particularly in connection with the manufacture of ethyl carbazol, it can nevertheless be extended generally to the manufacture of alkyl, ar 1 or alkaryl carbazols that are I capable of being made by the action of a halogen -containing organic compound ion potassiumcarba'zol. l ypical specific exam}; ples of such other carbazol derivatives that R90 6213;: be manufacimed by the naval QIOCGSS hereimbavia descmbed me h'yi cm'bazui and earmwl,

The *rmess 02f mamlfaeturhmeth a itating a mixsfium potassium carbm Z01, die' zhyi sulfate and 1mm m reaction is substantially complete, driving benzene, and optiimakiy purifying; the rresmltimt ethyl carbazoh l'n testimony whereof I hereunta nr ii-z.

WELLZAi-vii 

